Qt中给LineEdit或ComboBox空间增加点击事件

本文记录Qt里给LineEdit、Label等普通控件增加点击事件的操作，常用的两种方法如下：

方法一

• 以LineEdit为例，增加子类继承QLineEdit类，重新实现mousePressEvent函数
  MyLineEdit.h

#ifndef MYLINEEDIT_H
#define MYLINEEDIT_H
#include <QObject>
#include <QLineEdit>
#include <QMouseEvent>

class MyLineEdit : public QLineEdit     
{
   
   
    Q_OBJECT     //记得要加，不然emit那行编译报错
public:
   explicit MyLineEdit(QWidget *parent = 0);
    ~MyLineEdit();
protected:
    virtual void mousePressEvent(QMouseEvent *e);
signals:
    void clicked();  //提供给外部的信号
};

#endif // MYLINEEDIT_H

MyLineEdit.cpp

#include "mylineedit.h"

MyLineEdit::MyLineEdit(QWidget *parent)
    :QLineEdit(parent)
{
   
   

}

MyLineEdit::~MyLineEdit